Frankie limits the hours during which the kids can voice their needs; Mike watches to make sure Darrin doesn't take advantage of Sue; Brick invites new friends over.
Shumway secretly orders one of the 100 to kill Bellamy. Meanwhile, hallucinogenic nuts provide Octavia with an opportunity to help the Grounder escape the camp, and Bellamy and Clarke investigate a nearby underground depot, where they find military weapons.
Truman, empowered with new authority from the President, launches a mustard gas attack designed to kill Miles and Monroe. To Rachel's disappointment, Miles agrees to join Monroe in a ruthless plot to beat the Patriots at their own game. As Neville faces his own challenge from the Patriots, Aaron grows increasingly alarmed by the power of the nanotech.
Elizabeth makes a shocking discovery about Kate. Philip pursues a contact for information about stealth. Stan continues his pursuit of the illegals.
Riley is looking forward to meeting Philip’s sister from England, but her excitement soon vanishes when it becomes obvious that Georgie is less than impressed by her brother’s taste in girlfriends. Danny’s contract negotiations are in jeopardy when Bonnie tangles with the Rangers’ new general manager, Valerie.
David, Gill and their son Freddie hope Noel Fitzpatrick can help their Labrador Scooby, who has a life-threatening tumour in his leg. The vet goes to extraordinary lengths to save the life of Tiger the cat after his heart stops during his recovery from an operation, and when a lurcher called Otis brought in with shotgun wounds, Noel must extract the bullet before working out how to save the animal's leg. Plus, will a pair of tights help a French bulldog walk again?
Hannah and Tom have happy news, and Derek's dad Anthony goes on a date with Tom's nan. But matters of the heart are taking a downward turn for Kev, who calls on his brother Cliff for help.
A man's online accounts are hacked by a woman he met on Facebook in the Season 3 premiere. After meeting Zoe on Facebook, she begins demanding passwords and hacking accounts.
Taylor is tempted at a party and the Cassidys go to Christian therapy. Meanwhile, Teryn and Chad finally renew their vows and Tori's parents stage an intervention for Tori.
Commander Perry notifies the Intelligence unit that Pulpo has been released to help track down a dangerous cartel leader. This doesn’t sit well with our team as he kidnapped one of their own and no love is lost between sides. Meanwhile, Ruzek gets some difficult news as a blast from Lindsay’s past comes back, giving us a glimpse at where she came from. Voight reminds her that she’s come too far to screw it up. At the same time we learn something about Jin that is bound to be a problem.
Boyce decides to cancels the annual bake sale after taking on a healthier lifestyle.
Mel has everything she needs for the perfect wedding after a close friend unexpectedly calls off her nuptials; Lennox helps Ryder construct an untruthful resume.
Tessa struggles with the budget while planning Lisa and Malik's wedding; June warns Tessa to stay away from Ryan; Malik turns to George when his family decides to boycott the wedding; Sheila gives Lisa advice.
Banished to Tonga to live with his uncle, 14-year-old Jonah is causing more trouble than ever. His dad takes him back to Sydney to start a new life but he quickly forms a new school gang and it's not long till trouble starts.
Jay, Gloria and Manny challenge each other to step outside their comfort zone and try something new. Mitch and Cam’s wedding is getting too big and costly so they resort to selling a couple of their prized possessions, and the kids play a joke on Phil and Claire.
The night is late and Bruce has yet to seal the deal with Jessica, so he decides to try something clever. Fab and Kacey both notice their handsome gynecologist and must decide which one of them gets to make a play for him. Liv and Ron decide to do something crazy and leave for a strip club.
The women attempt to adopt a dog but a shelter volunteer manages ruin their plans. Elka's relationships with Mamie and Roy take a surprising twist.
During an intense challenge, castaways attempt to crack the code and earn a spot in the Final Five. Additionally, one castaway's paranoia threatens another's stake in the game, and Tony's closest confidant is wooed by another alliance.